Biodiversity Terms

A glossary of definitions for terms relating to biodiversity, ecosystems services and conservation.

All definitions are referenced, where possible preference has been given to internationally recognised definitions (for example those defined by international conventions or agreements). The terms have been chosen to support understanding of biodiversity and conservation issues, and terms relating to biodiversity loss are complemented by those relating to conservation responses supported by international conservation organisations, governments, scientists and business sectors.

More detailed explanations are provided for a number of key terms, to provide further background information.

The terms can be filtered by category to aid in the navigation of the many definitions.

In-situ conservation

Definition

The conservation of ecosystems and natural habitats and the maintenance and recovery of viable populations of species in their natural surroundings and, in the case of domesticated or cultivated species, in the surroundings where they have developed their distinctive properties.

Contents

In-situ conservation is one of two basic conservation strategies, alongside ex-situ conservation. Article 8 of the Convention on Biological Diversity (CBD) specifies in-situ conservation as the primary conservation strategy, and states that ex-situ measures should play a supportive role to reach conservation targets.

In-situ conservation aims to enable biodiversity to maintain itself within the context of the ecosystem in which it is found.

In-situ management approaches can either be targeted at populations of selected species (species-centred) or whole ecosystems (ecosystem-based).

Traditionally, protected areas have been seen as the cornerstone of in-situ conservation. Conservation approaches that are more adaptable to individual situations and applicable beyond protected areas, are being increasingly applied.

In-situ (‘on site’, ‘in place’) conservation is a set of conservation techniques involving the designation, management and monitoring of biodiversity in the same area where it is encountered.
The in-situ concept is best understood in contrast to ex-situ conservation. Ex-situ (‘off site’) conservation techniques are implemented away from the conservation target's natural habitat. While the identification of ex-situ initiatives leaves little room for ambiguity (e.g. zoos, seed banks, captive breeding), the notion of in-situ conservation covers a broad spectrum of situations ranging from the establishment of a protected area to the design of a sustainable management strategy for a particular habitat.

In-situ management approaches can either be targeted at populations of selected species (species-centred approaches), or whole ecosystems (ecosystem-based approaches)2. Both approaches follow the same purpose: To enable biodiversity to maintain itself within the context of the ecosystem in which it has been found, ie. to enable a species population to self-replicate and maintain its potential for continued evolution3. This requires conservation of the components of the natural system (populations, species, communities and biophysical systems) as well as the ecological and evolutionary processes occurring within that system.
Conservation measures are aimed at the surroundings where a target-species developed its distinctive properties. This could be a natural habitat, or an environment heavily modified by human activity. For instance, agricultural or domestic species may have evolved characteristic traits in human dominated environments. The conservation of agricultural biodiversity therefore requires the conservation of agro-ecosystems by farmers, commonly using traditional farming practices2,4.

Protected areas are the cornerstone of in-situ conservation, as is outlined in Article 8 of the CBD. A protected area network may contribute to conservation targets through the maintenance of target species and their habitats, as well as the conservation of natural or semi-natural ecosystems.
There is a however growing awareness of the importance of extending in-situ conservation beyond protected areas5,6. The socioeconomic and political context around a threatened habitat may prevent the establishment or success of a protected area, and the development of alternative in-situ conservation management approaches may prove more useful in these situations. For instance, it was shown that the protection of Indonesian coral reefs could be enhanced through the implementation of a management plan which included a cycle of open and closed harvesting of reef resources within prescribed locations7.
In-situ initiatives beyond protected areas may include2,5:

Historically, in-situ conservation was the preferred biodiversity conservation approach over ex-situ conservation10. In-situ measures are perceived as more holistic in their approach and allow the conservation of processes or habitats which can’t be protected through ex-situ measures (e.g. soil microbial processes, evolutionary processes, specific ecosystems such as coral reefs or species with highly specialised needs). The Convention on Biological Diversity (CBD) recognizes the complementary role of both conservation strategies (in-situ and ex-situ). Article 8 and 9 of the CBD set out guidelines for the use of in-situ and ex-situ measures, respectively. In particular, the CBD specifies that ex-situ facilities and techniques should predominantly be implemented for the purpose of complementing and supporting in-situ measures11.